The Firing Pin offers full service Gunsmithing and Firearm Restoration, Specializing in Color Case Hardening or Case Color Hardening (w/bone & charcoal), cleaning, hot bluing, rust bluing and rust browning.
The Firing Pin
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I'm familiar with carburization, boriding and nitriding, but I had to Google bone and charcoal. Seems pretty interesting. I always wondered how they got the really neat coloring effect on old rifles and pistols.
Do you recommend bone and charcoal for modern firearms?